Multimodal Fundus Imaging of Outer Retinal Tubulations after Ranibizumab Injections in Choroidal Osteoma

Purpose: To report the development and to evaluate findings in multimodal imaging of outer retinal tubulations (ORTs) shown in all five eyes with inactivate choroidal neovascular membrane after treatment with ranibizumab in patients with choroidal osteoma. Methods: Four eyes from two healthy young male patients with confirmed diagnosis of bilateral choroidal osteoma and 39-year-old woman with unilateral choroidal osteoma and a history of decreased vision underwent full clinical and imaging assessments. Identifying in all four eyes an active choroidal neovascularization membrane and treated with intravitreal injections of ranibizumab. Color fundus photography, spectral domain optical coherence tomography (Spectralis HRA+OCT; Heidelberg, Germany) and optical coherence tomography angiography (RTVue-XR; Optovue, Inc, Fremont,CA) were performed to identify and analyzed characteristics of ORTs. Results: Optical coherence tomography showed the presence of choroidal osteoma and choroidal neovascularization with subretinal fluid. After treatment with intravitreal injection of ranibizumab and complete disappearance of subretinal fluid, all five eyes with choroidal osteoma showed ORTs. The ORTs were located above or very close to scar or fibrosis area of the choroidal neovascular membrane (CNVM), with no evidence of subretinal fluid. Conclusion: The result in this series of cases suggests the presence of ORTs after inactivation of choroidal neovascularization membrane with ranibizumab treatment in all eyes with choroidal osteoma. The formation of outer retinal tubulations (ORTs) might be explained by the theory that surviving photoreceptors can establish new lateral connections with nearby cells in response after retinal injury. As well, clinicians should be careful to differentiate the morphology between OTRs and intraretinal fluid caused by choroidal neovascular membrane, as OTRs does not benefit from intraocular anti vascular endothelial growth factor (VEGF) injections.